Drilling apparatus having head

ABSTRACT

Disclosed is a drilling apparatus having a head. The drilling apparatus includes a main body, a lead supported by the main body of the drilling apparatus, a driving shaft slidably installed in the lead and having a unit rod connected thereto for performing a drilling work, and a head having an actuator for driving the driving shaft, wherein the driving shaft includes a screw coupling part formed on the outer circumferential surface of the driving shaft and screw-coupled with an end of the unit rod for performing the drilling work, and a screw coupling inducing part formed at a front end of the screw coupling part to induce screw coupling between the driving shaft and a rod screw coupling part formed at a hollow part formed at the end of the unit rod. The drilling apparatus can reduce the number of work numbers by combining the unit rod with the driving shaft, thereby increasing the efficiency of the drilling work.

TECHNICAL FIELD

The present invention relates to a drilling apparatus, and more particularly, to a drilling apparatus having a head, which facilitates engagement or disengagement between a rod and a driving shaft installed in the head when a drilling work is performed using a bit.

BACKGROUND ART

In general, a drilling apparatus is used to excavate deep holes into the ground for purposes of boring, soil testing or development of underground water. The drilling apparatus is classified into a type in which a boring work is performed while rotating a rod having a bit, and a type in which a boring work is performed by rotating a rod having a bit or a cutter and striking the bit or the cutter using the rod.

A conventional drilling apparatus is disclosed in Korean Patent No. 624233. The disclosed drilling apparatus comprises a main body having a driving device such as an engine, a leader supported by the main body, and a head sliding along the leader and generating an elevational force or a rotational force by a driving device provided in the main body, a rod coupled to the head and elevating or rotating by the head, and a drill unit provided at a front end of the rod and perforate the ground while elevating or rotating along with the rod.

The drill unit includes a bit striking and drilling the ground and a hammer operated by a hydraulic pressure to apply a striking force to the beat. The drilling apparatus is configured to drill the ground to a predetermined depth such that the bit of the drill unit rotates or strikes the ground.

As the excavated depth increases in the course of drilling, the drilling work is performed by connecting unit rods to allow a drill unit to excavate the ground deeper and deeper. The unit rods are connected such that a driving shaft of a head is separated from the unit rod currently performing the drilling work and then connected to a new unit rod to perform a drilling work.

In the course of drilling, if the unit rods have relatively small diameters, it is difficult to align the driving shaft of the head with the unit rod. In particular, even if the unit rod and the driving shaft are coaxially aligned, it is not easy to screw-couple the unit rod to the driving shaft. Thus, it is impossible to increase the efficiency of the drilling work due to a trouble in screw-coupling of the unit rod and the driving shaft.

Meanwhile, a support pipe is installed to prevent a landslide during the drilling work. As the drill unit and the unit rod are inserted into the ground to a gradually increasing depth, it is necessary to connect the support pipe. Since there is no separate means for balancing the support pipe, the support pipe may vibrate or may not be aligned with the center of a rotation shaft. Therefore, it is necessary to adjust the support pipe installed on the ground when the support pipe is connected.

DISCLOSURE OF THE INVENTION

In order to overcome the above-mentioned shortcomings, the present invention provides a drilling apparatus having a head, which facilitates engagement or disengagement between a rod and a driving shaft of the head when a drilling work is performed, thereby increasing the efficiency in the drilling work.

The present invention also provides a drilling apparatus having a head, which enables engagement between a driving shaft and a unit rod according to the diameter of the unit rod connected to the driving shaft.

According to an aspect of the invention, there is provided a drilling apparatus having a head, including a main body, a lead supported by the main body of the drilling apparatus, a driving shaft slidably installed in the lead and having a unit rod connected thereto for performing drilling work, and a head having an actuator for driving the driving shaft, wherein the driving shaft includes a screw coupling part formed on the outer circumferential surface of the driving shaft and screw-coupled with an end of the unit rod for performing the drilling work, and a screw coupling inducing part formed at a front end of the screw coupling part to induce screw coupling between the driving shaft and a rod screw coupling part formed at a hollow part formed at the end of the unit rod.

A stopper may be provided on the outer circumferential surface of a top end of the screw coupling part of the driving shaft for preventing the unit rod screw-coupled to the driving shaft from elevating.

The screw coupling induction part may include a taper part extending from the screw coupling part of the driving shaft to an end of the screw coupling induction part and having diameters gradually decreasing.

According to another aspect of the invention, there is provided a drilling apparatus having a head, including a main body, a lead supported by the main body of the drilling apparatus, a driving shaft slidably installed in the lead and having a unit rod connected thereto for performing drilling work, and a head having an actuator for driving the driving shaft, wherein the driving shaft includes a first driving shaft supported on the head body by a bearing and exposed to a bottom end of the head body, and a second driving shaft having a screw coupling part screw-coupled coaxially with the first driving shaft and screw-coupled with an end of the unit rod for performing the drilling work, and a screw coupling inducing part formed at a front end of the screw coupling part to induce screw coupling between the driving shaft and a rod screw coupling part formed at a hollow part formed at the end of the unit rod.

The first driving shaft may include stepped coupling parts having different diameters, and a plurality of second driving shafts having different diameters to be selectively coupled to the coupling parts of the first driving shaft.

As described above, in the drilling apparatus having a head according to the present invention, the unit rod and the driving shaft can be easily engaged with each other during a drilling work, thereby increasing the efficiency of the drilling work.

BRIEF DESCRIPTION OF THE DRAWINGS

The objects, features and advantages of the present invention will be more apparent from the following detailed description in conjunction with the accompanying drawings, in which:

FIG. 1 is a side view of a drilling apparatus having a head according to the present invention;

FIG. 2 is a cross-sectional view of the drilling apparatus shown in FIG. 1;

FIG. 3 is an exploded perspective view of a driving shaft according to an embodiment of the present invention;

FIGS. 4 and 5 are perspective views of driving shafts according to another embodiment of the present invention; and

FIG. 6 is a perspective view illustrating a state in which a driving shaft and a unit rod are engaged with each other.

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

The drilling apparatus according to the present invention facilitates engagement between a unit rod and a driving shaft of the head when the ground hole is excavated, and en exemplary embodiment of the drilling apparatus is shown in FIGS. 1 to 5.

Referring to FIGS. 1 to 5, the drilling apparatus 100 having a head includes a lead 20 supported by a main body 10, a driving shaft 40 slidably installed in the lead 20 and connected to the topmost unit rod among the unit rods 70 connected to each other for drilling work, a head 30 having an actuator (not shown) for driving the driving shaft 40, and a support pipe 200 installed on the ground for preventing earth and sand around a hole excavated by the lead from collapsing.

The head 30 slidably installed along the lead 20 and is configured to elevate by a separate driver (although not shown, the driver including sprockets installed at top and bottom portions of the lead 20, a chain locked on the sprockets and having one side fixed to the head 30, and a hydraulic motor driving one of the sprockets). As shown in FIG. 2, a hydraulic motor 33 for driving the driving shaft 40 rotatably supported by the bearing 32 is installed in a main body 31 of the head 30. The hydraulic motor 33 receives hydraulic oil by a hydraulic supply system installed in the main body 10 to then be driven.

As shown in FIGS. 2 and 3, the driving shaft 40 includes a screw coupling part 41 and a screw coupling inducing part 42. The screw coupling part 41 is formed on the outer circumferential surface of the driving shaft 40 and is screw-coupled to an end of the unit rod 70 for performing a drilling work. The screw coupling inducing part 42 is formed at a front end of the screw coupling part 41 to smoothly achieve screw coupling between the driving shaft 40 and a rod screw coupling part 73 formed at a hollow part 70 a at the end of the unit rod 70. A stopper 43 is formed on the outer circumferential surface of the driving shaft 40 at a top end of the driving shaft 40, corresponding to a terminating end of the screw coupling part 41, to prevent the unit rod 70 screw-coupled to the screw coupling part 41 from being damaged while rotating.

The stopper 43 may include a protrusion formed on the outer circumferential surface of the driving shaft 40, but aspects of the present invention are not limited thereto.

The hollow part 40 a is formed at the driving shaft 40 in a lengthwise direction. The screw coupling inducing part 42 may be tapered upwardly from its end. That is to say, a diameter of an end of the screw coupling induction part 42 is smaller than that of the driving shaft 40. Smooth surfaces 45 and 46 symmetrical about the center of the driving shaft 40 are provided at one or more sides of the screw coupling part 41 or the screw coupling inducing part 42. When the driving shaft 40 includes first and second driving shafts to be described later, the smooth surfaces 45 and 46 are provided for engagement or disengagement of the first driving shaft and the second driving shaft.

FIG. 4 illustrates a head driving shaft of a drilling apparatus according to another embodiment of the present invention.

Referring to FIG. 4, a head driving shaft 50 is supported on the head body 31 by a bearing 32 to be rotatably installed, and includes a first driving shaft 51 formed at an end exposed to a bottom end of the head body 31 and a second driving shaft 55 combined with the first driving shaft 51.

The first driving shaft 51 may include stepped coupling parts 51 a, 51 b and 51 c having different diameters. Screws for being coupled to the second driving shaft 55 are formed on the outer circumferential surfaces of the coupling parts 51 a, 51 b and 51 c.

The second driving shaft 55 may include a plurality of second driving shafts having different diameters (corresponding to diameters of unit rods) to be engaged with the coupling parts 51 a, 51 b and 51 c of the first driving shaft 51. The second driving shafts 55 having different diameters are provided for the purpose of being compatibly used when the unit rods for performing a drilling work have different diameters.

The second driving shaft 55 may include a coupling screw part 56, a screw coupling part 57 and a screw coupling inducing part 58. The coupling screw part 56 is formed on the inner circumferential surface of the second driving shaft 55 to be coaxially coupled to the first driving shaft 51, the screw coupling part 57 is formed on the outer circumferential surface of the second driving shaft 55 to be screw-coupled to the rod screw coupling part 73 of the unit rod 70, and the screw coupling inducing part 58 extends from the screw coupling part 57. As described above, the screw coupling inducing part 58 is tapered such that its diameter gradually decreases from the screw coupling part 57 to its end. The end of the screw coupling induction part 58 may be spherical to facilitate insertion of the hollow part 70 a of the unit rod 70 into the screw coupling induction part 58. A hollow part 40 a is formed in a lengthwise direction of the first and second driving shafts 51 and 55.

As shown in FIG. 5, the first and second driving shafts 51 and 55 may be coupled to the first and second driving shafts 51 and 55 by flange parts 61 and 62.

A stopper 59 may be installed in the second driving shaft 55 to prevent the unit rod 70 coupled to the second driving shaft 55 and performing a drilling work from elevating while rotating. A position adjusting unit (not shown) may further be provided at an upper portion of the stopper 59 to hold the support pipe 200 inserted into an excavated portion for preventing earth and sand existing around the excavated portion from collapsing. The position adjusting unit is tapered such that its upper side has a larger diameter than the support pipe 200.

The aforementioned drilling apparatus operates as follows.

As shown in FIGS. 1 and 6, in order to excavate an underground hole using the drilling apparatus according to the present invention, the drilling apparatus is positioned at a portion where the ground hole is to be formed, and the lead 20 is vertically positioned on the portion where the ground hole is to be formed. In such a state, the head 30 is positioned on the lead 20 and the unit rod 70 is then connected to the driving shaft 40. An air hammer or a water hammer 80 for performing a drilling work is installed at a bottom end of the unit rod 70.

The unit rod 70 and the driving shaft 40 are engaged with each other such that the unit rod 70 is suspended using a crane (not shown), the screw coupling induction part 42 of the driving shaft 40 is inserted into the hollow part 70 a of the unit rod 70, and the driving shaft 40 is rotated while moving the unit rod 70 and the driving shaft 40 with respect to each other. In such a manner, in a state in which the screw coupling induction part 42 extending from the screw coupling part 41 of the driving shaft 40 is inserted into the hollow part 70 a of the unit rod 70, the screw coupling part 41 is guided to the rod screw coupling part 73 of the unit rod 70, thereby facilitating engagement of the unit rod 70 and the driving shaft 40, which will now be described in more detail. Since the screw coupling induction part 42 provided at the driving shaft 40 has a diameter gradually decreasing from the screw coupling part 41, even if the unit rod 70 and the driving shaft 40 are not aligned in line, the screw coupling induction part 42 can be easily inserted into the hollow part 70 a of the unit rod 70.

Therefore, the problem associated with the conventional drilling apparatus, that is, the necessity for making the end of the unit rod 70 and the driving shaft 40 coincide with each other by an operator's manual work, can be solved. In particular, when the unit rod 70 has a small diameter and a small thickness, engagement of the unit rod 70 and the driving shaft 40 can be smoothly achieved by being guided by the screw coupling induction part 42.

The above-described operation is achieved in the same manner as in engagement of the second driving shafts 55 and the unit rod 70. In particular, as shown in FIG. 4, the coupling parts 51 a, 51 b and 51 c formed in multiple-steps are provided in the first driving shaft 51, and the second driving shafts 55 suited to diameters of the respective coupling parts 51 a, 51 b and 51 c are provided, thereby allowing the second driving shafts 55 to be compatibly used according to the diameters of the unit rods for performing a drilling work.

Meanwhile, the stopper 43 for preventing the unit rod 70 from elevating due to a rotational force of the driving shaft 40 when the unit rod 70 is screw-coupled is provided at the driving shaft 40. Thus, even if a rotational load is applied to the unit rod 70 during a drilling work, it is possible to prevent the unit rod 70 from elevating along the screw coupling part 41 of the driving shaft 40. It is also possible to prevent the unit rod 70 screw-coupled to the screw coupling part 41 from being damaged due to the rotational load applied thereto while rotating. That is to say, the unit rod 70 can be prevented from being damaged, which may be caused when the unit rod 70 elevates to a portion of the driving shaft 40 without screws due to the rotational load.

In addition, the position adjusting unit for balancing the support pipe 200 installed for drilling soft ground is further provided at the driving shaft 40. When the head 30 is lowered, the position adjusting unit is inserted into the support pipe 200, thereby aligning centers of the support pipe 200 and the driving shaft 40. Therefore, it is possible to prevent the center of the support pipe 2000 from deviating from the center of the unit rod 70 while the drilling work is performed.

Although exemplary embodiments of the present invention have been described in detail hereinabove, it should be understood that many variations and modifications of the basic inventive concept herein described, which may appear to those skilled in the art, will still fall within the spirit and scope of the exemplary embodiments of the present invention as defined by the appended claims. 

What is claimed is:
 1. A drilling apparatus having a head, comprising: a main body; a lead supported by the main body of the drilling apparatus; a driving shaft slidably installed in the lead and having a unit rod connected thereto for performing a drilling work; and a head having an actuator for driving the driving shaft, wherein the driving shaft includes a screw coupling part formed on the outer circumferential surface of the driving shaft and screw-coupled with an end of the unit rod for performing the drilling work, and a screw coupling inducing part formed at a front end of the screw coupling part to induce screw coupling between the driving shaft and a rod screw coupling part formed at a hollow part formed at the end of the unit rod.
 2. The drilling apparatus of claim 1, wherein a stopper is provided on the outer circumferential surface of a top end of the screw coupling part of the driving shaft for preventing the unit rod screw-coupled to the driving shaft from elevating.
 3. The drilling apparatus of claim 1, wherein the screw coupling induction part includes a taper part extending from the screw coupling part of the driving shaft to an end of the screw coupling induction part and having diameters gradually decreasing.
 4. A drilling apparatus having a head, comprising: a main body; a lead supported by the main body of the drilling apparatus; a driving shaft slidably installed in the lead and having a unit rod connected thereto for performing a drilling work; and a head having an actuator for driving the driving shaft, wherein the driving shaft includes a first driving shaft supported on the head body by a bearing and exposed to a bottom end of the head body, and a second driving shaft having a screw coupling part screw-coupled coaxially with the first driving shaft and screw-coupled with an end of the unit rod for performing the drilling work, and a screw coupling inducing part formed at a front end of the screw coupling part to induce screw coupling between the driving shaft and a rod screw coupling part formed at a hollow part formed at the end of the unit rod.
 5. The drilling apparatus of claim 4, wherein the first driving shaft includes stepped coupling parts having different diameters, and a plurality of second driving shafts having different diameters to be selectively coupled to the coupling parts of the first driving shaft. 